X-Git-Url: https://svn.cri.ensmp.fr/git/linpy.git/blobdiff_plain/9b755b94aa2c8847ffca607de239f5c3bca9984b..5541da1f6a0d044cf6ea335d5cf338964310b4ad:/examples/tesseract.py?ds=sidebyside diff --git a/examples/tesseract.py b/examples/tesseract.py index b2a5e97..383d7bd 100755 --- a/examples/tesseract.py +++ b/examples/tesseract.py @@ -1,23 +1,25 @@ #!/usr/bin/env python3 -from pypol import * +# In geometry, the tesseract is the four-dimensional analog of the cube; the +# tesseract is to the cube as the cube is to the square. Just as the surface of +# the cube consists of 6 square faces, the hypersurface of the tesseract +# consists of 8 cubical cells. + +from linpy import * + x, y, z, t = symbols('x y z t') -tesseract = \ - Le(0, x) & Le(x, 1) & \ - Le(0, y) & Le(y, 1) & \ - Le(0, z) & Le(z, 1) & \ - Le(0, t) & Le(t, 1) +tesseract = Le(0, x, 1) & Le(0, y, 1) & Le(0, z, 1) & Le(0, t, 1) def faces(polyhedron): for points in polyhedron.faces(): face = points[0].aspolyhedron() - face = face.union(*[point.aspolyhedron() for point in points[1:]]) - face = face.aspolyhedron() + face = face.convex_union(*[point.aspolyhedron() for point in points[1:]]) yield face -print('Faces of tesseract\n\n {}\n\nare:\n'.format(tesseract)) -for face in faces(tesseract): - assert(len(face.vertices()) == 8) - print(' {}'.format(face)) +if __name__ == '__main__': + print('Faces of tesseract\n\n {}\n\nare:\n'.format(tesseract)) + for face in faces(tesseract): + assert(len(face.vertices()) == 8) + print(' {}'.format(face))